Protests erupt in Brazil after release of Rousseff-Lula recording

Protests have erupted in Brazil after a recorded phone call between President Dilma Rousseff and her once-popular predecessor was released, suggesting that she appointed him to her cabinet to spare him from arrest for corruption.

Rousseff appointed Luiz Inacio Lula da Silva as her chief of staff on March 16 hoping that his political prowess can save her administration. The president is battling an impeachment attempt, a deep recession, and the fallout of an explosive corruption scandal at state oil giant Petrobras.

However hours after Lula's appointment, federal judge Sergio Moro, who is heading a probe into the Petrobras scandal, ordered the release of a call recorded by police suggesting darker motives.

Rousseff called Lula's bugged phone to tell him she would be sending him the official decree nominating him as her chief of staff so that he could make use of it "if necessary." 

That extract seems to confirm that Lula's nomination to the post was aimed at sparing him possible arrest for corruption.

Cabinet ministers can only be tried before the Supreme Court in Brazil, and ministerial immunity will now protect Lula from prosecution in criminal court.

Lula vigorously denies involvement in the scandal, in which investigators say construction companies conspired with Petrobras executives to overbill the oil giant to the tune of $2 billion, paying huge bribes to politicians and parties along the way.

Rousseff's office said the phone call was merely to discuss a procedural matter.

The recording's release caused an uproar in Congress, where furious opposition lawmakers shouted "Resign! Resign!" 

Some 2,000 people spontaneously gathered in the capital Brasilia to demand that Lula step down...